If you've got some successful keyword research and PPC advertising under your belt for your own website, why not capitalize on that and make money online without one? Affiliate marketing through pay-per-click makes it possible. Learn how to make money today.

MSN adCenter and Yahoo Search Marketing both allow direct linking to sites that are not your own. (But don't try this with Google AdWords.)

Direct linking means that you can join affiliate programs, create ads for their products, and send click-throughs directly to the merchant's site. There's no need to build an intermediary site or use your own site to direct traffic. When your click-throughs convert, you get a commission.

It's a way to create an extra stream of income--or several--with some big advantages:

It eliminates the time, effort, and costs of building and maintaining web pages. The only time you'll have to pay is when someone clicks on your ad.

It allows you to do affiliate marketing without cluttering up your own site with links that might send potential customers away. You can keep your site clean and focused on its job of selling your product, but still make commissions off other people's products.

It eliminates an extra click for users. One click less for them means more commissions for you.

While direct linking is a good opportunity, though, it's not a walk in the park. The PPC programs that allow it restrict the number of affiliate ads that can point at the same display URL that shows on the ad itself. So ads by experienced affiliate marketers who know exactly what they're doing can bump less skillful ads.

If you want your ads to be seen, here's what you have to do.

Step 1: Start with a big, broad marketChoose a broad market where there's a lot of searching going on. You want to get as many eyeballs as possible.

Step 2: Do some keyword researchDon't build your ads on broad, untargeted keywords, though. The competition for those will be fierce--and expensive. Your objective here is to find neglected, low-cost keywords within a broad, high-traffic market--and that's why it really helps to have keyword research experience.

And as I mentioned in an earlier article, you need to look for specific problems that are shared by a lot of people within a market. Then find relevant keyword terms that clearly show a clear intention to buy or find out more information. Those terms are much more likely to convert. And remember, you pay for every click, but you get paid only when they convert.

The Microsoft Advertising Intelligence tool can show you almost anything you'd like to know about any given keyword, including similar keywords, traffic, cost per click, and much more. The free Google AdWords Keyword Tool is also a quick and handy way of getting ideas for keywords with high search volume and low cost per click; just keep in mind that you can't use this strategy with Google.

Step 3: Find a good affiliate merchant that targets your nicheIn order to find a merchant that offers a relevant product and pays you a good commission, check out these affiliate networks and directories:

Do they offer a product that directly solves a problem you've identified?

Do they allow direct linking to their sites? Some don't. Check the terms and conditions before you commit.

Does the landing page generate pop-ups? If so, then forget it. This is not allowed. The back button on the page also has to be functional.

Is there a strong landing page for the product? If you send click-throughs to an irrelevant page, a confusing sales process, or a site that's just plain unappealing, then they won't convert and you'll end up wasting your money.

Step 4: Write a PPC ad that drives buyers to the affiliate merchant's siteTake a good look at the landing page your ad is pointing at and make your ad directly relevant to it. Your ad must:

address the specific problem you've identified.

include the keyword you've bid on, preferably more than once.

reflect the keywords of the landing page.

highlight a benefit of the product.

include a strong call to action.

You can give your ad an extra boost by adding your keyword, or part of it, to the display URL at the bottom of the ad. The actual target URL will contain a big, ugly affiliate ID number, but the display version can show the domain name plus a subdirectory with a word or phrase that makes it look relevant to the search, like this:

Before you create your display link, check out the PPC competition to make sure it's unique so your ad won't be bumped. The better your ads, the higher the click-throughs will be, which means your ads will be rewarded with better positions for the same money. It's worth polishing them, and then testing them to see which ones are performing the best.

Running a pay-per-click affiliate campaign probably won't generate hundreds of thousands of dollars for you right off the bat--but it is the easiest way to leverage the keyword research and PPC skills you've developed in building your own site. And when Microsoft adCenter and Yahoo Search Marketing join forces sometime this year, you'll get the traffic from both, even if you only advertise on one. That makes direct linking even more appealing.

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